Q: Intermittently doesn't start

asked by on October 16, 2016

Intermittently cranks but doesnt start thinking ECU but dont know what other model cars use the LYU 2, LYU 3, LYU 4 It runs no problem for 2days or 3 & out of blue cranks but dont start changed a few things & it works 2-3 days then back to beginning also when done trying to crank & i turn key back it backfires
My car has a manual transmission.

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Hi there. There could be several reasons for your vehicle’s intermittent no start issue. From the description you have given, I would not think the ECU (electronic control unit) is your vehicle’s problem. Assuming the ECU is not recognizing the fault, I would look in the direction of a possible intermittent ignition module failure.

The cranking and turning the key back which results in backfiring could be a faulty ignition switch. It could also be an intermittent control relay problem(https://www.yourmechanic.com/services/fuel-pump-relay-replacement). I recommend having your vehicle’s intermittent no start issue be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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